1. Field of the Invention
This invention relates to headlamps for vehicles, and more particularly to three different aspects: cushioning against impact; removable for use as an emergency light; and changing the color of the light emitted.
2. The State of the Art
One of the most prevalent problems with headlamps is impact damage during low speed collisions, such as when in a parking lot or in slow moving traffic. Various bumper and other front end structures, such as described in U.S. Pat. Nos. 5,010,456, 5,288,177, 5,651,604, 6,190,030, and 6,331,068, are devised to deform and protect the headlamp during a collision. Various headlamp mounting assemblies, such as described in U.S. Pat. No. 4,356,539, include leaf springs, but such are not designed to provide any significant movement of the headlamp and thus do not cushion the impact. On the other hand, U.S. Pat. No. 4,658,335 describes a rear lamp mounted on a leaf spring and depending from a truck bumper to provide a resilient connection for the lamp. However, there are no aftermarket products than can be used with existing vehicles to retrofit a headlamp to be more resilient to impact.
Regarding vehicles in general, when a driver needs to pull off to the side of the road to fix a flat tire, typically the only lighting available is the ambient lighting from street lamps and oncoming vehicles. Flashlights and similar devices are sold which are powered by batteries, so one must be sure that the batteries are fresh and have not leaked. Other flashlights and similar devices can be powered by DC current available through the cigarette lighter socket, but their light output is relatively limited.
In yet another aspect, the color of the headlamp can make the lighting more effective and/or less distracting/imposing for on-coming traffic. In many European countries, headlamps have a yellow cast, likely because the wavelength is more energetic and can penetrate fog better, and is less blinding that pure white light. Accordingly, it would be beneficial to change the light emanating from the headlamp depending on the driving conditions (weather and ambient/street lighting) and the amount and/or type of oncoming traffic. U.S. Pat. Nos. 4,041,302 and 4,153,928 describe, respectively, a vehicle tail lamp having one color and selecting a different color when the bulb is not energized, and a vehicle tail lamp that appears black when the bulb is not energized. Systems for controlling headlight intensity or energization based on oncoming traffic are well known (e.g., U.S. Pat. No. 5,527,003). U.S. Pat. No. 5,725,296 describes the use of a light pipe as a remote lighting source, and the ability to colorize the light to the remote source, but such a device may not be readily amenable to aftermarket sale where customers are interested more in buying existing lamps or new lamps that can be used in the same manner as the existing lamp.